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What is Geometry? Geometry is the study of shapes They studied Geometry in Ancient Mesopotamia & Ancient Egypt Geometry is important in the art and construction fields

Points An exact position or location

POINT A POINT is an exact location on a graph, shape or in “space”. The Hershey Kiss is a POINT on the line ●

LINE A LINE goes in opposite directions and never, never, never ends. Imagine if this Twizzler went on forever and ever and ever and ever and ever and ever

RAY A RAY is part of a line, but it has one endpoint and the other end keeps going. ● Raaaaaaaaaaaaaaaaaaaaaaaayyyyyyyyyyyyyyyyyyyyyyyyyyy Endpoint

ENDPOINT An ENDPOINT is a point at the end of a ray or line segment.

LINE SEGMENT A LINE SEGMENT is part of a ray or line. It has two endpoints Line Segment Line ● ● Line ● Endpoints Ray

Lines and Rays LINE: A straight path extending in both directions with no endpoints LINE SEGMENT: A part of a line that includes two points, called endpoints, and all the points between them RAY: A part of a line, with one endpoint, that continues without end in one direction

VERTEX A VERTEX is a fancy name for “angle” Two rays or lines that have the same endpoint make a VERTEX/angle VERTEX/angles are measured in “degrees” When two lines cross, they make vertex/angles The Corners of a square are its vertex/angles

CONGRUENT CONGRUENT means the “same” CONGRUENT LINE SEGMENTS means two line segments are the same CONGRUENT Vertex/Angles means two angles are the same ● ● ● ● The Hershey & Crunch Bar are a Congruent size

VERTICAL LINE A VERTICAL LINE goes up & down The candy bars are vertical

HORIZONTAL LINE A HORIZONTAL LINE goes “across” (left and right) The candy bars are Horizontal

More about Lines INTERSECTING LINES: Lines that cross PARALLEL LINES: Lines that never cross and are always the same distance apart

Perpendicular Lines Two lines that intersect to form four right angles

OPEN & CLOSED FIGURES A CLOSED FIGURE/SHAPE starts and ends at the same point. An OPEN FIGURE/SHAPE does NOT start and end at the same point. CLOSED OPEN Start Start ● ● ● End End

POLYGON A POLYGON is a “closed” shape A POLYGON is made up of line segments that do not cross. The number of sides gives a POLYGON its name NOT POLYGON POLYGON

Angles The figure formed when two rays share the same endpoint Acute Angle: An angle less than a right angle Obtuse Angle: An angle greater than a right angle Right Angle: An angle that forms a square corner

3 TYPES OF ANGLES ACUTE ANGLES are less than 90°

3 TYPES OF ANGLES RIGHT ANGLES measure exactly 90 ° The “square” symbol means 90’

Right Angle or Not? Not! Not! Right Angle Not! Right Angle Not!

3 TYPES OF ANGLES OBTUES ANGLES are greater than 90 ° but less than 180 °

ANGLES When you “name” an angle. The vertex/angle “letter/number” goes in the center of the label B A C If I wanted to know the measurement of Angle A…I would ask:” What is the measurement for BAC?” (Notice A is in the center)